Many in the scientific community have long assumed that nest-building in birds is a purely instinctive skill — an inborn ability that birds repeat from one nest to the next, regardless of their personal building history.

But now, an international team of researchers in Botswana has observed birds engaging in behavior that suggests they may actually learn from experience, a finding that flies in the face of many widely-held assumptions about nest-building and bird cognition.

When it comes to architecturally inclined birds, Botswana's Southern Masked Weaver is one of the most prolific; Weaver birds like the one pictured up top are not only known to build dozens of nests in a single season, their nests also tend to be relatively complex. These characteristics allowed for researchers from Scotland and Botswana to monitor changes in the nest-building techniques of individual Weavers over extended periods of time.

The researchers found that individual birds not only varied their design technique from one nest to the next (assembling their nests first from left to right, then from right to left, for example), they also became better builders as the season progressed — completing various stages of nest construction more quickly and dropping fewer and fewer of their building materials as they gained more and more experience.

According to the scientists, these "experience-dependent changes" support the hypothesis that — at least in the Southern Masked Weaver — the art of nest-building may actually require learning.

University of Edinburgh biologist Patrick Walsh, who participated in the study, explains the significance of the team's findings:

If birds built their nests according to a genetic template, you would expect all birds to build their nests the same way each time. However this was not the case. Southern Masked Weaver birds displayed strong variations in their approach, revealing a clear role for experience. Even for birds, practice makes perfect.